Via my typed notes from his 2007 USC Commencement Speech:
Wisdom acquisition is a moral duty. It’s not something you do just to advance in life. As a corollary to that proposition which is very important, it means that you are hooked for lifetime learning. And without lifetime learning, you people are not going to do very well. You are not going to get very far in life based on what you already know. You’re going to advance in life by what you learn after you leave here.
I constantly see people rise in life who are not the smartest, sometimes not even the most diligent, but they are learning machines. They go to bed every night a little wiser than they were when they got up and boy does that help, particularly when you have a long run ahead of you.
…so if civilization can progress only with an advanced method of invention, you can progress only when you learn the method of learning.
Nothing has served me better in my long life than continuous learning.
I went through life constantly practicing (because if you don’t practice it, you lose it) the multi-disciplinary approach and I can’t tell you what that’s done for me. It’s made life more fun, it’s made me more constructive, its made me more helpful to others, its made me enormously rich. You name it, that attitude really helps. Now, there are dangers in it because it works so well that if you do it, you will frequently find you’re sitting in the presence of some other expert, maybe even an expert superior to you (supervising you), and you’ll know more than he does about his own specialty, a lot more. You’ll see the correct answer and he’s missed it. That is a very dangerous position to be in. You can cause enormous offense by being right in a way that causes somebody else to lose face. And I never found a perfect way to solve that problem. My advice to you is to learn sometimes to keep your light under a bushel.
Marcus Cicero is famous for saying that the man who doesn’t know what happened before he was born goes through life like a child. That is a very correct idea. If you generalize Cicero, as I think one should, there are all these other things that you should know in addition to history. And those other things are the big ideas in all the other disciplines. It doesn’t help just to know them enough so you can [repeat] them back on an exam and get an A. You have to learn these things in such a way that they’re in a mental latticework in your head and you automatically use them for the rest of your life. If you do that I solemnly promise you that one day you’ll be walking down the street and you’ll look to your right and left and you’ll think “my heavenly days, I’m now one of the of the few most competent people in my whole age cohort.” If you don’t do it, many of the brightest of you will live in the middle ranks or in the shallows.